These folks all were flying on a plane together. The island is sunk (which would have happened according the the final episode if the MIB got off the island). They talk to each other, they touch each other, they interact.

But then we go to the end of the season and they are all going to a church. That we have never seen before, that has no relevance to the story or the peoples experiences. But somehow they have built it as a place they would join together and go on to the new life.

HUH?????? That makes no sense at all.

If the island is sunk, they should be infected with evil, if we go by the importance of the island and what was happening when it was "uncorked". But somehow in never, never land, everything is fine.

They don't see each other on a plane that they are all together on AND was the catalyst for all of this, but they build a church. On the island, Eko and Charlie tried to build a church, but it was abandoned.